This invention relates generally to medical devices and more particularly to devices for introducing a catheter or other elongated instrument into the body of a living being via a percutaneous incision or puncture.
Various introducer devices are disclosed in the patent literature and many are commercially available for effecting the introduction of a catheter or some other instrument through a percutaneous incision or puncture into the body, e.g., an artery, of a living being. Such devices commonly make use of some hemostatic valve mechanism to ensure that blood does not flow out of the introducer when it is in place. Examples of such devices are found in the following U.S. Pat. Nos.: 3,459,183 (Ring et al), 4,000,739 (Stevens), 4,424,833 (Spector et al), 4,430,181 (Timmermans), 4,610,665 (Matsumoto et al) 4,610,674 (Suzuki et al), 4,626,245 (Weinstein), 4,655,752 (Honkanen et al), 4,723,550 (Boles et al), 4,726,374 (Boles et al), 4,874,378 (Hillstead), 4,895,565 (Hillstead), 4,929,235 (Merry et al), and 5,000,745 (Guest et al). The valve mechanisms used in such device typically comprise one or more valve components formed of an elastomeric material having one or more slits or apertures therein to enable a catheter or some other instrument to be inserted therethrough, with the slit(s) or aperture(s) sealing closed after the catheter or instrument has been removed therefrom. The elastomeric materials making up the prior art valve components typically exhibit a relatively high coefficient of friction. Thus, prior art introducers have tended to be somewhat resistant to the easy passage of a catheter or other instrument therethrough. In order to facilitate the passage of the instrument through prior art valve members, i.e., to reduce the friction therethrough, some prior art introducers utilize fluid lubricants, e.g. silicone, impregnated in the material making up the valve member.
While such prior art devices are generally suitable for their intended purposes they never the less still leave something to be desired from the standpoints of facilitating the introduction of delicate instruments therethrough, while ensuring that a good hemostatic seal exists to prevent the outflow of blood from the introducer.